The present application relates to the fixing of rotary pistons of a rotary piston pump on the respective drive shaft.
Rotary piston pumps are self-priming or conditionally self-priming valveless positive displacement pumps with rotary pistons engaging into one another. In particular, rotary piston pumps comprise at least two counter-rotating double- or multi-lobe rotary pistons, the drive shafts whereof comprise seals. Rotary piston pumps preferably comprise two drive shafts for two rotary pistons.
According to DE 19806657, the drive shafts are provided at their end arranged in the pump space with screw joints for fastening to the rotary pistons. The drive shafts are each constituted in one piece and remain in the pump housing during the assembly or dismantling of the rotary pistons. Provision is made here such that one of the drive shafts is connected via a coupling to the drive and is freely rotatable with respect to the other drive shaft in the uncoupled state.
DE 102012003066 B3 describes a method and a device for fixing and synchronising rotary pistons of a rotary piston pump. Here, the rotary pistons are introduced in the pump space. A shaft stub of each rotary piston is pushed through the pump rear wall onto the respective drive shaft. The rotary pistons are aligned and synchronised in the pump space by means of a template. The template is fixed detachably to the pump housing in this alignment step. The shaft stubs of the aligned rotary pistons are each connected by means of a clamping device in a friction-locked manner to the respective drive shaft outside the pump space.
DE 102013101185 A1 discloses a rotary piston pump, wherein the seals are arranged on a shaft shoulder of the respective rotary piston and one slip ring per seal is provided with a locking device, which comprises a multiplicity of fixing positions. The seal with the locking device is pushed onto the tubular shaft shoulder and the shaft shoulder of each rotary piston is pushed through the pump rear wall onto the respective drive shaft. By rotating the rotary piston, a securing element is connected in a form-fit manner in axial grooves of the locking device. The shaft shoulder and therefore the rotary piston are then connected by a clamping device in a friction-locked manner to the respective drive shaft outside the pump space.
The problem of the invention is to fix the rotary pistons of a rotary piston pump easily and quickly on the respective drive shaft, so that torques and axial forces are transmitted play-free from the drive shaft into the rotary piston.
The above problem is solved by a rotary piston pump, a method for fixing rotary pistons of an aforementioned rotary piston pump and a method for dismantling rotary pistons of an aforementioned rotary piston pump, according to the invention.